To facilitate microscopic examination of pathology tissue specimens, tissue specimens are typically treated with processing fluids, encased in a block of paraffin, and then sliced into thin sections. This process is carried out by placing each tissue specimen in a tissue processing cassette. Such cassettes used for pathology tissue specimens for microscopic examination are well known. While tissue processing cassettes vary in design, tissue processing cassettes generally include an open-topped base having a perforated bottom wall and a removable perforated cover. The cassettes are generally fabricated of a moldable plastic that resists damage or reaction from processing solvents or the tissue specimen itself.
To process a tissue specimen for examination, the tissue specimen is placed into the base of the cassette and the cover is secured to the base. The cassette and the tissue specimen are then placed in a tissue cassette processing container where various processing fluids are passed into the cassette for the purpose of dehydrating the specimen, clearing the specimen, and infiltrating the specimen with molten paraffin. After this process is completed, the cover is removed from the base and the specimen is taken from the base and placed in a tissue embedding mold.
The tissue embedding mold is typically constructed of stainless steel and configured to support the specimen in a lower portion thereof and to support the base of the cassette in an upper portion thereof. With the specimen and the base positioned in the mold, the mold is filled via the perforations of the base of the cassette with liquid paraffin or some other suitable encasing material. Upon the paraffin solidifying, the specimen becomes encased within a block of paraffin which extends from the base of the cassette. The base and the block of paraffin can then be mounted in a microtome where a section of the tissue specimen can be sliced for microscopic examination.
After a paraffin-encased tissue specimen is removed from the mold, the mold needs to be cleaned thoroughly before the mold can be used again. In the past, workers have cleaned molds by placing them in a bath of heated xylene. Unfortunately, xylene is highly flammable and thus presents an obvious fire and explosive danger.
Thus, there is a need for a method by which the tissue processing molds can be cleaned without creating a fire or explosive danger. It is to such a method that the present invention is directed.